Effective metal screening and Schottky-barrier formation in metal-GaAs structures

Author

Wu, X. ; Yang, Edward S.

Author_Institution

Dept. of Electr. Eng., Columbia Univ., New York, NY, USA

Volume

11

Issue

7

fYear

1990

fDate

7/1/1990 12:00:00 AM

Firstpage

315

Lastpage

317

Abstract

The Fermi-level movement in a Schottky barrier is investigated using a bimetal thin-film structure. The functional dependence of the barrier height on the inner metal thickness is formulated in terms of the metal effective screening length and the interface trap states. This model is used to describe experimental results on Pt-Ti-GaAs and Ti-Pt-GaAs diodes. It is found that the effective screening lengths for Pt and Ti are 6.5 and 7.0 AA, respectively, significantly greater than the ideal values of the theory of N.F. Mott and H. Jones (1958). This indicates that the potential drop inside the metal electrode can evolve over several monolayers in a Schottky contact.<>

Keywords

III-V semiconductors; Schottky effect; Schottky-barrier diodes; gallium arsenide; semiconductor device models; semiconductor-metal boundaries; Fermi-level movement; Pt-Ti-GaAs diodes; Schottky contact; Schottky-barrier formation; Ti-Pt-GaAs diodes; barrier height; bimetal thin-film structure; experimental results; inner metal thickness; interface trap states; metal effective screening length; model; potential drop; semiconductors; Atomic layer deposition; Electrodes; Gallium arsenide; Interface states; Schottky barriers; Schottky diodes; Semiconductor diodes; Semiconductor-metal interfaces; Surface treatment; Transistors;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/55.56486

Filename

56486